Organic electroluminescence display device and manufacturing method thereof

ABSTRACT

An organic electroluminescence display includes a first substrate with a pixel region formed with an organic electroluminescence element including a first electrode, an organic thin film layer and a second electrode and a non-pixel region formed with a metal wiring for transmitting signals from the exterior to the organic electroluminescence element, a second substrate arranged in a upper side of the first substrate, a frit provided between the first and second substrates, and a first and a second protective films provided as a stacking structure between the metal wiring and the frit, wherein the first substrate and the second substrate are attached to each other through the frit. The metal wirings of the non-pixel region have a first protective film made of a silicon compound formed thereon.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of Korean Patent Application Nos.10-2006-0014324, filed on Feb. 14, 2006, and 10-2006-0020108, filed onMar. 2, 2006 in the Korean Intellectual Property Office, the disclosuresof which are incorporated herein by reference in its entirety.

BACKGROUND

1. Field

The invention relates to an organic electroluminescence display deviceand a manufacturing method thereof, and more specifically, to an organicelectroluminescence display device encapsulated by a frit and amanufacturing method thereof.

2. Discussion of the Related Technology

In general, organic electroluminescence display devices comprise asubstrate on which a pixel region and a non-pixel region are provided,and a vessel or another substrate arranged to be opposite to thesubstrate and attached to the substrate by a sealant such as epoxy forits encapsulation.

On the pixel region of the substrate are formed multiple light-emittingelements connected in a matrix form between a scan line and a data line,the light-emitting elements comprising an anode electrode and cathodeelectrode, and an organic thin film layer formed between the anodeelectrode and cathode electrode, the organic thin film layer comprisingan hole transport layer, an organic light-emitting layer and an electrontransport layer.

The light-emitting elements configured as described above aresusceptible to oxygen exposure because of they contain organicmaterials. They are also easily oxidized by moisture in the air sincethe cathode electrode is made of metal materials and can sufferdeterioration to electrical and light-emitting properties. To mitigatethe above problems, a powder-type moisture absorbent or a film-typemoisture absorbent on a vessel manufactured in the form of a metalmaterial can or cup, or a substrate made of glass, plastic, etc. isprovided to take up moisture, oxygen and hydrogen penetrated from theexterior.

However, such a method of coating the powder-type moisture absorbentrequires complicated processes and raises cost for materials and theprocesses. In addition, the method results in an increase of thethickness of the display device and further it is difficult to beapplied to an screen light-emitting type. In addition, the method ofattaching the film-type moisture absorbent has limited ability toeliminate all the moisture and also has low durability and reliability,thus limiting application in the production in large quantities. Theabove discussion is simply to describe the general field of organiclight emitting displays and is not a discussion of the prior art.

Methods have been employed which encapsulates light-emitting elements byforming side walls with frits to overcome the afore-mentioned problems.

International patent application No. PCT/KR2002/000994 (May 24, 2002)discloses an encapsuation container formed with side walls using a glassfrit and a manufacturing method thereof.

U.S. patent application Ser. No. 10/414,794 (Apr. 16, 2003) discloses aglass package encapsulated by attaching a first and a second glassplates through a frit and a manufacturing method thereof.

Korean patent laying-open gazette No. 2001-0084380 (Sep. 6, 2001)discloses a frit frame encapsulation method using a laser.

Korean patent laying-open gazette No. 2002-0051153 (Jun. 28, 2002)discloses a packaging method of encapsulating an upper substrate and alower substrate with a frit layer using a laser.

SUMMARY OF CERTAIN INVENTIVE ASPECTS

Embodiments of the invention is to provide an organicelectroluminescence display device which allows for inhibiting damage tometal wirings due to heat by stopping the metal wirings of a lower sideof a frit and a part intersecting the frit from be directly exposed toheat due to laser beam, and a manufacturing method thereof.

An organic electroluminescence display device according to oneembodiment comprises a first substrate formed with an organicelectroluminescence element comprising a first electrode, an organicthin film layer and a second electrode and a metal wiring fortransmitting signals to the organic electroluminescence element, asecond substrate arranged in a upper side of the first substrate, a fritprovided between the first substrate and the second substrate, and aprotective film formed of the first electrode material between the metalwiring and the frit, the protective film separated from the firstelectrode.

An organic electroluminescence display device according to anotherembodiment comprises a first substrate formed with an organicelectroluminescence element comprising a first electrode, an organicthin film layer and a second electrode, a transistor for controlling theoperation of the organic electroluminescence element and a metal wiringfor transmitting signals to the organic electroluminescence element, asecond substrate arranged in a upper side of the first substrate, a fritprovided between the first substrate and the second substrate, and aprotective film formed of the first electrode material between the metalwiring and the frit, the protective film separated from the firstelectrode.

An organic electroluminescence display device according to still anotherembodiment comprises a first substrate defining a pixel region formedwith an organic electroluminescence element comprising a firstelectrode, an organic thin film layer and a second electrode anddefining a non-pixel region formed with a metal wiring for transmittingsignals from the exterior to the organic electroluminescence element, asecond substrate arranged in a upper side of the first substrate, a fritprovided between the first substrate and the second substrate, and afirst and a second protective films provided as a stacking structurebetween the metal wiring and the frit, wherein the first substrate andthe second substrate are attached to each other through the frit.

An organic electroluminescence display device according to yet anotherembodiment comprises a first substrate comprising a pixel region formedwith an organic electroluminescence element comprising a firstelectrode, an organic thin film layer and a second electrode and atransistor connected to the first electrode, the transistor comprising asource, a drain and a gate, and a non-pixel region formed with a metalwiring for transmitting signals from the exterior to the organicelectroluminescence element, a second substrate arranged in a upper sideof the first substrate, a frit provided between the first substrate andthe second substrate, and a first and a second protective films providedas a stacking structure between the metal wiring and the frit, whereinthe first substrate and the second substrate are attached to each otherthrough the frit.

A manufacturing method of an organic electroluminescence display deviceaccording to one embodiment comprises the steps of providing a bufferlayer on a first substrate including a pixel region and a non-pixelregion, providing a semiconductor layer on the buffer layer of the pixelregion and providing a gate insulating film on the upper surface of thenon-pixel region, providing a gate electrode and a first metal wiring onthe gate insulating film of the pixel region and providing on the gateinsulating film of the non-pixel region the first metal wiring extendedfrom the first metal wiring of the pixel region, providing abetween-layer insulating film on the upper surface of the pixel regionand non-pixel region and providing a contact hole so that a portion ofthe semiconductor layer is exposed, providing on the between-layerinsulating film of the pixel region a source and drain electrodes and asecond metal wiring connected through the contact hole to thesemiconductor layer and providing on the between-layer insulating filmof the non-pixel region the second metal wiring extended from the secondmetal wiring of the pixel region, providing a flattened layer on theupper surface of the pixel region and providing a via hole so that thesource and drain electrodes are exposed, providing an inorganicelectrode layer on the upper surface of the pixel region and non-pixelregion and then patterning the inorganic electrode layer, with a firstelectrode formed on the pixel region, the first electrode connectedthrough the via hole to the source or drain electrode, and with aprotective film formed on the non-pixel regin, providing an organic thinfilm layer and a second electrode on the first electrode, forming a fritalong a surrounding of the second substrate, and arranging the secondsubstrate on an upper surface of the first substrate and then attachingthe frit to the first substrate.

A manufacturing method of an organic electroluminescence display deviceaccording to another embodiment comprises the steps of forming a bufferlayer on a first substrate of a pixel region and a non-pixel region,forming a semiconductor layer on the buffer layer of the pixel regionand then forming a gate insulating film on the upper surface of thepixel region and the non-pixel region, forming a gate electrode and afirst metal wiring on the gate insulating film of the pixel region andforming on the gate insulating film of the non-pixel region the firstmetal wiring and a pad extended from the first metal wiring of the pixelregion, forming a between-layer insulating film on the upper surface ofthe pixel region and then forming a contact hole so that a portion ofthe semiconductor layer is exposed, forming on the between-layerinsulating film of the pixel region a source and drain electrodes and asecond metal wiring connected through the contact hole to thesemiconductor layer and forming on the gate insulating film of thenon-pixel region the second metal wiring and pad extended from thesecond metal wiring of the pixel region, forming a first protective filmon the upper surface of the non-pixel region including the first andsecond metal wirings, forming a flattened layer on the upper surface ofthe pixel region and then forming a via hole so that the source anddrain electrodes are exposed, forming an inorganic electrode layer onthe upper surface of the pixel region and non-pixel region and thenpatterning the inorganic electrode layer, with a first electrode formedon the pixel region, the first electrode connected through the via holeto the source or drain electrode, and with a second protective filmformed on the non-pixel regin, forming an organic thin film layer and asecond electrode on the first electrode to form an organicelectroluminescence element, preparing a second substrate formed withthe frit along a surrounding of the second substrate, and arranging thesecond substrate on an upper surface of the first substrate and thenattaching the frit to the first substrate.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other aspects and advantages of the invention will becomeapparent and more readily appreciated from the following description ofthe preferred embodiments, taken in conjunction with the accompanyingdrawings of which:

FIG. 1 is a picture for illustrating damage to a metal wiring byirradiating a laser beam.

FIGS. 2 a, 3 a and 4 are plan views of illustrating an organicelectroluminescence display device according to a first embodiment ofthe invention.

FIGS. 2 b and 3 b are sectional views for illustrating FIGS. 2 a and 3a.

FIGS. 5 a through 5 g and FIG. 7 are plan views of illustrating amanufacturing method of an organic electroluminescence display deviceaccording to a first embodiment of the invention.

FIGS. 6 a and 6 b are plan views for illustrating FIGS. 5 a and 5 e.

FIGS. 8 a and 8 b are an enlarged sectional view and a plan view ofregion ‘A’ circled in FIG. 7.

FIGS. 9 a, 10 a and 11 are plan views of illustrating an organicelectroluminescence display device according to a second embodiment ofthe invention.

FIGS. 9 b and 10 b are sectional views for illustrating FIGS. 9 a and 10a.

FIGS. 12 a through 12 h and FIG. 14 are plan views of illustrating amanufacturing method of an organic electroluminescence display deviceaccording to a second embodiment of the invention.

FIGS. 13 a and 13 b are plan views for illustrating FIGS. 12 a and 12 g.

FIGS. 15 a and 15 b are enlarged sectional views of region ‘B’ circledin FIG. 14.

FIG. 16 is a schematic exploded view of a passive matrix type organiclight emitting display device in accordance with one embodiment.

FIG. 17 is a schematic exploded view of an active matrix type organiclight emitting display device in accordance with one embodiment.

FIG. 18 is a schematic top plan view of an organic light emittingdisplay in accordance with one embodiment.

FIG. 19 is a cross-sectional view of the organic light emitting displayof FIG. 18, taken along the line 19-19.

FIG. 20 is a schematic perspective view illustrating mass production oforganic light emitting devices in accordance with one embodiment.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

A method for encapsulating a light emitting element using a frit, whichattaches a substrate on which the frit is coated to another substrate onwhich light emitting elements are formed, and then causes the frit to befused and attached to the substrates by illuminating a laser beam, has alimitation in that when the laser beam is irradiated to the frit, metalwirings 10 of a lower part of the frit 20 and a part (region ‘A’)intersecting the frit may be directly exposed to heat due to the laserbeam, which can possibly result in heat damage. Heat damaged metalwirings may develop cracks, and/or their self resistance and electricalproperties can be changed, thus affecting the electrical property andreliability of elements.

Certain embodiments provide an organic electroluminescence displaydevice addressing these limitations, and a manufacturing method thereof.Embodiments of the invention will be described in a more detailed mannerwith reference to the accompanying drawings. It should be understoodthat the following embodiments will be provided to allow those skilledin the art to fully understand the invention, but the invention is notlimited thereto, and various modifications can be made.

An organic light emitting display (OLED) is a display device comprisingan array of organic light emitting diodes. Organic light emitting diodesare solid state devices which include an organic material and areadapted to generate and emit light when appropriate electricalpotentials are applied.

OLEDs can be generally grouped into two basic types dependent on thearrangement with which the stimulating electrical current is provided.FIG. 16 schematically illustrates an exploded view of a simplifiedstructure of a passive matrix type OLED 1000. FIG. 17 schematicallyillustrates a simplified structure of an active matrix type OLED 1001.In both configurations, the OLED 1000, 1001 includes OLED pixels builtover a substrate 1002, and the OLED pixels include an anode 1004, acathode 1006 and an organic layer 1010. When an appropriate electricalcurrent is applied to the anode 1004, electric current flows through thepixels and visible light is emitted from the organic layer.

Referring to FIG. 16, the passive matrix OLED (PMOLED) design includeselongate strips of anode 1004 arranged generally perpendicular toelongate strips of cathode 1006 with organic layers interposedtherebetween. The intersections of the strips of cathode 1006 and anode1004 define individual OLED pixels where light is generated and emittedupon appropriate excitation of the corresponding strips of anode 1004and cathode 1006. PMOLEDs provide the advantage of relatively simplefabrication.

Referring to FIG. 17, the active matrix OLED (AMOLED) includes localdriving circuits 1012 arranged between the substrate 1002 and an arrayof OLED pixels. An individual pixel of AMOLEDs is defined between thecommon cathode 1006 and an anode 1004, which is electrically isolatedfrom other anodes. Each driving circuit 1012 is coupled with an anode1004 of the OLED pixels and further coupled with a data line 1016 and ascan line 1018. In embodiments, the scan lines 1018 supply scan signalsthat select rows of the driving circuits, and the data lines 1016 supplydata signals for particular driving circuits. The data signals and scansignals stimulate the local driving circuits 1012, which excite theanodes 1004 so as to emit light from their corresponding pixels.

In the illustrated AMOLED, the local driving circuits 1012, the datalines 1016 and scan lines 1018 are buried in a planarization layer 1014,which is interposed between the pixel array and the substrate 1002. Theplanarization layer 1014 provides a planar top surface on which theorganic light emitting pixel array is formed. The planarization layer1014 may be formed of organic or inorganic materials, and formed of twoor more layers although shown as a single layer. The local drivingcircuits 1012 are typically formed with thin film transistors (TFT) andarranged in a grid or array under the OLED pixel array. The localdriving circuits 1012 may be at least partly made of organic materials,including organic TFT. AMOLEDs have the advantage of fast response timeimproving their desirability for use in displaying data signals. Also,AMOLEDs have the advantages of consuming less power than passive matrixOLEDs.

Referring to common features of the PMOLED and AMOLED designs, thesubstrate 1002 provides structural support for the OLED pixels andcircuits. In various embodiments, the substrate 1002 can comprise rigidor flexible materials as well as opaque or transparent materials, suchas plastic, glass, and/or foil. As noted above, each OLED pixel or diodeis formed with the anode 1004, cathode 1006 and organic layer 1010interposed therebetween. When an appropriate electrical current isapplied to the anode 1004, the cathode 1006 injects electrons and theanode 1004 injects holes. In certain embodiments, the anode 1004 andcathode 1006 are inverted; i.e., the cathode is formed on the substrate1002 and the anode is opposingly arranged.

Interposed between the cathode 1006 and anode 1004 are one or moreorganic layers. More specifically, at least one emissive or lightemitting layer is interposed between the cathode 1006 and anode 1004.The light emitting layer may comprise one or more light emitting organiccompounds. Typically, the light emitting layer is configured to emitvisible light in a single color such as blue, green, red or white. Inthe illustrated embodiment, one organic layer 1010 is formed between thecathode 1006 and anode 1004 and acts as a light emitting layer.Additional layers, which can be formed between the anode 1004 andcathode 1006, can include a hole transporting layer, a hole injectionlayer, an electron transporting layer and an electron injection layer.

Hole transporting and/or injection layers can be interposed between thelight emitting layer 1010 and the anode 1004. Electron transportingand/or injecting layers can be interposed between the cathode 1006 andthe light emitting layer 1010. The electron injection layer facilitatesinjection of electrons from the cathode 1006 toward the light emittinglayer 1010 by reducing the work function for injecting electrons fromthe cathode 1006. Similarly, the hole injection layer facilitatesinjection of holes from the anode 1004 toward the light emitting layer1010. The hole and electron transporting layers facilitate movement ofthe carriers injected from the respective electrodes toward the lightemitting layer.

In some embodiments, a single layer may serve both electron injectionand transportation functions or both hole injection and transportationfunctions. In some embodiments, one or more of these layers are lacking.In some embodiments, one or more organic layers are doped with one ormore materials that help injection and/or transportation of thecarriers. In embodiments where only one organic layer is formed betweenthe cathode and anode, the organic layer may include not only an organiclight emitting compound but also certain functional materials that helpinjection or transportation of carriers within that layer.

There are numerous organic materials that have been developed for use inthese layers including the light emitting layer. Also, numerous otherorganic materials for use in these layers are being developed. In someembodiments, these organic materials may be macromolecules includingoligomers and polymers. In some embodiments, the organic materials forthese layers may be relatively small molecules. The skilled artisan willbe able to select appropriate materials for each of these layers in viewof the desired functions of the individual layers and the materials forthe neighboring layers in particular designs.

In operation, an electrical circuit provides appropriate potentialbetween the cathode 1006 and anode 1004. This results in an electricalcurrent flowing from the anode 1004 to the cathode 1006 via theinterposed organic layer(s). In one embodiment, the cathode 1006provides electrons to the adjacent organic layer 1010. The anode 1004injects holes to the organic layer 1010. The holes and electronsrecombine in the organic layer 1010 and generate energy particles called“excitons.” The excitons transfer their energy to the organic lightemitting material in the organic layer 1010, and the energy is used toemit visible light from the organic light emitting material. Thespectral characteristics of light generated and emitted by the OLED1000, 1001 depend on the nature and composition of organic molecules inthe organic layer(s). The composition of the one or more organic layerscan be selected to suit the needs of a particular application by one ofordinary skill in the art.

OLED devices can also be categorized based on the direction of the lightemission. In one type referred to as “top emission” type, OLED devicesemit light and display images through the cathode or top electrode 1006.In these embodiments, the cathode 1006 is made of a material transparentor at least partially transparent with respect to visible light. Incertain embodiments, to avoid losing any light that can pass through theanode or bottom electrode 1004, the anode may be made of a materialsubstantially reflective of the visible light. A second type of OLEDdevices emits light through the anode or bottom electrode 1004 and iscalled “bottom emission” type. In the bottom emission type OLED devices,the anode 1004 is made of a material which is at least partiallytransparent with respect to visible light. Often, in bottom emissiontype OLED devices, the cathode 1006 is made of a material substantiallyreflective of the visible light. A third type of OLED devices emitslight in two directions, e.g. through both anode 1004 and cathode 1006.Depending upon the direction(s) of the light emission, the substrate maybe formed of a material which is transparent, opaque or reflective ofvisible light.

In many embodiments, an OLED pixel array 1021 comprising a plurality oforganic light emitting pixels is arranged over a substrate 1002 as shownin FIG. 18. In embodiments, the pixels in the array 1021 are controlledto be turned on and off by a driving circuit (not shown), and theplurality of the pixels as a whole displays information or image on thearray 1021. In certain embodiments, the OLED pixel array 1021 isarranged with respect to other components, such as drive and controlelectronics to define a display region and a non-display region. Inthese embodiments, the display region refers to the area of thesubstrate 1002 where OLED pixel array 1021 is formed. The non-displayregion refers to the remaining areas of the substrate 1002. Inembodiments, the non-display region can contain logic and/or powersupply circuitry. It will be understood that there will be at leastportions of control/drive circuit elements arranged within the displayregion. For example, in PMOLEDs, conductive components will extend intothe display region to provide appropriate potential to the anode andcathodes. In AMOLEDs, local driving circuits and data/scan lines coupledwith the driving circuits will extend into the display region to driveand control the individual pixels of the AMOLEDs.

One design and fabrication consideration in OLED devices is that certainorganic material layers of OLED devices can suffer damage or accelerateddeterioration from exposure to water, oxygen or other harmful gases.Accordingly, it is generally understood that OLED devices be sealed orencapsulated to inhibit exposure to moisture and oxygen or other harmfulgases found in a manufacturing or operational environment. FIG. 19schematically illustrates a cross-section of an encapsulated OLED device1011 having a layout of FIG. 18 and taken along the line 19-19 of FIG.18. In this embodiment, a generally planar top plate or substrate 1061engages with a seal 1071 which further engages with a bottom plate orsubstrate 1002 to enclose or encapsulate the OLED pixel array 1021. Inother embodiments, one or more layers are formed on the top plate 1061or bottom plate 1002, and the seal 1071 is coupled with the bottom ortop substrate 1002, 1061 via such a layer. In the illustratedembodiment, the seal 1071 extends along the periphery of the OLED pixelarray 1021 or the bottom or top plate 1002, 1061.

In embodiments, the seal 1071 is made of a frit material as will befurther discussed below. In various embodiments, the top and bottomplates 1061, 1002 comprise materials such as plastics, glass and/ormetal foils which can provide a barrier to passage of oxygen and/orwater to thereby protect the OLED pixel array 1021 from exposure tothese substances. In embodiments, at least one of the top plate 1061 andthe bottom plate 1002 are formed of a substantially transparentmaterial.

To lengthen the life time of OLED devices 1011, it is generally desiredthat seal 1071 and the top and bottom plates 1061, 1002 provide asubstantially non-permeable seal to oxygen and water vapor and provide asubstantially hermetically enclosed space 1081. In certain applications,it is indicated that the seal 1071 of a frit material in combinationwith the top and bottom plates 1061, 1002 provide a barrier to oxygen ofless than approximately 10⁻³ cc/m²-day and to water of less than 10⁻⁶g/m²-day. Given that some oxygen and moisture can permeate into theenclosed space 1081, in some embodiments, a material that can take upoxygen and/or moisture is formed within the enclosed space 1081.

The seal 1071 has a width W, which is its thickness in a directionparallel to a surface of the top or bottom substrate 1061, 1002 as shownin FIG. 19. The width varies among embodiments and ranges from about 300μm to about 3000 μm, optionally from about 500 μm to about 1500 μm.Also, the width may vary at different positions of the seal 1071. Insome embodiments, the width of the seal 1071 may be the largest wherethe seal 1071 contacts one of the bottom and top substrate 1002, 1061 ora layer formed thereon. The width may be the smallest where the seal1071 contacts the other. The width variation in a single cross-sectionof the seal 1071 relates to the cross-sectional shape of the seal 1071and other design parameters.

The seal 1071 has a height H, which is its thickness in a directionperpendicular to a surface of the top or bottom substrate 1061, 1002 asshown in FIG. 19. The height varies among embodiments and ranges fromabout 2 μm to about 30 μm, optionally from about 10 μm to about 15 μm.Generally, the height does not significantly vary at different positionsof the seal 1071. However, in certain embodiments, the height of theseal 1071 may vary at different positions thereof.

In the illustrated embodiment, the seal 1071 has a generally rectangularcross-section. In other embodiments, however, the seal 1071 can haveother various cross-sectional shapes such as a generally squarecross-section, a generally trapezoidal cross-section, a cross-sectionwith one or more rounded edges, or other configuration as indicated bythe needs of a given application. To improve hermeticity, it isgenerally desired to increase the interfacial area where the seal 1071directly contacts the bottom or top substrate 1002, 1061 or a layerformed thereon. In some embodiments, the shape of the seal can bedesigned such that the interfacial area can be increased.

The seal 1071 can be arranged immediately adjacent the OLED array 1021,and in other embodiments, the seal 1071 is spaced some distance from theOLED array 1021. In certain embodiment, the seal 1071 comprisesgenerally linear segments that are connected together to surround theOLED array 1021. Such linear segments of the seal 1071 can extend, incertain embodiments, generally parallel to respective boundaries of theOLED array 1021. In other embodiment, one or more of the linear segmentsof the seal 1071 are arranged in a non-parallel relationship withrespective boundaries of the OLED array 1021. In yet other embodiments,at least part of the seal 1071 extends between the top plate 1061 andbottom plate 1002 in a curvilinear manner.

As noted above, in certain embodiments, the seal 1071 is formed using afrit material or simply “frit” or glass frit,” which includes fine glassparticles. The frit particles includes one or more of magnesium oxide(MgO), calcium oxide (CaO), barium oxide (BaO), lithium oxide (Li₂O),sodium oxide (Na₂O), potassium oxide (K₂O), boron oxide (B₂O₃), vanadiumoxide (V₂O₅), zinc oxide (ZnO), tellurium oxide (TeO₂), aluminum oxide(Al₂O₃), silicon dioxide (SiO₂), lead oxide (PbO), tin oxide (SnO),phosphorous oxide (P₂O₅), ruthenium oxide (Ru₂O), rubidium oxide (Rb₂O),rhodium oxide (Rh₂O), ferrite oxide (Fe₂O₃), copper oxide (CuO),titanium oxide (TiO₂), tungsten oxide (WO₃), bismuth oxide (Bi₂O₃),antimony oxide (Sb₂O₃), lead-borate glass, tin-phosphate glass, vanadateglass, and borosilicate, etc. In embodiments, these particles range insize from about 2 μm to about 30 μm, optionally about 5 μm to about 10μm, although not limited only thereto. The particles can be as large asabout the distance between the top and bottom substrates 1061, 1002 orany layers formed on these substrates where the frit seal 1071 contacts.

The frit material used to form the seal 1071 can also include one ormore filler or additive materials. The filler or additive materials canbe provided to adjust an overall thermal expansion characteristic of theseal 1071 and/or to adjust the absorption characteristics of the seal1071 for selected frequencies of incident radiant energy. The filler oradditive material(s) can also include inversion and/or additive fillersto adjust a coefficient of thermal expansion of the frit. For example,the filler or additive materials can include transition metals, such aschromium (Cr), iron (Fe), manganese (Mn), cobalt (Co), copper (Cu),and/or vanadium. Additional materials for the filler or additivesinclude ZnSiO₄, PbTiO₃, ZrO₂, eucryptite.

In embodiments, a frit material as a dry composition contains glassparticles from about 20 to 90 about wt %, and the remaining includesfillers and/or additives. In some embodiments, the frit paste containsabout 10-30 wt % organic materials and about 70-90% inorganic materials.In some embodiments, the frit paste contains about 20 wt % organicmaterials and about 80 wt % inorganic materials. In some embodiments,the organic materials may include about 0-30 wt % binder(s) and about70-100 wt % solvent(s). In some embodiments, about 10 wt % is binder(s)and about 90 wt % is solvent(s) among the organic materials. In someembodiments, the inorganic materials may include about 0-10 wt %additives, about 20-40 wt % fillers and about 50-80 wt % glass powder.In some embodiments, about 0-5 wt % is additive(s), about 25-30 wt % isfiller(s) and about 65-75 wt % is the glass powder among the inorganicmaterials.

In forming a frit seal, a liquid material is added to the dry fritmaterial to form a frit paste. Any organic or inorganic solvent with orwithout additives can be used as the liquid material. In embodiments,the solvent includes one or more organic compounds. For example,applicable organic compounds are ethyl cellulose, nitro cellulose,hydroxyl propyl cellulose, butyl carbitol acetate, terpineol, butylcellusolve, acrylate compounds. Then, the thus formed frit paste can beapplied to form a shape of the seal 1071 on the top and/or bottom plate1061, 1002.

In one exemplary embodiment, a shape of the seal 1071 is initiallyformed from the frit paste and interposed between the top plate 1061 andthe bottom plate 1002. The seal 1071 can in certain embodiments bepre-cured or pre-sintered to one of the top plate and bottom plate 1061,1002. Following assembly of the top plate 1061 and the bottom plate 1002with the seal 1071 interposed therebetween, portions of the seal 1071are selectively heated such that the frit material forming the seal 1071at least partially melts. The seal 1071 is then allowed to resolidify toform a secure joint between the top plate 1061 and the bottom plate 1002to thereby inhibit exposure of the enclosed OLED pixel array 1021 tooxygen or water.

In embodiments, the selective heating of the frit seal is carried out byirradiation of light, such as a laser or directed infrared lamp. Aspreviously noted, the frit material forming the seal 1071 can becombined with one or more additives or filler such as species selectedfor improved absorption of the irradiated light to facilitate heatingand melting of the frit material to form the seal 1071.

In some embodiments, OLED devices 1011 are mass produced. In anembodiment illustrated in FIG. 20, a plurality of separate OLED arrays1021 is formed on a common bottom substrate 1101. In the illustratedembodiment, each OLED array 1021 is surrounded by a shaped frit to formthe seal 1071. In embodiments, common top substrate (not shown) isplaced over the common bottom substrate 1101 and the structures formedthereon such that the OLED arrays 1021 and the shaped frit paste areinterposed between the common bottom substrate 1101 and the common topsubstrate. The OLED arrays 1021 are encapsulated and sealed, such as viathe previously described enclosure process for a single OLED displaydevice. The resulting product includes a plurality of OLED devices kepttogether by the common bottom and top substrates. Then, the resultingproduct is cut into a plurality of pieces, each of which constitutes anOLED device 1011 of FIG. 19. In certain embodiments, the individual OLEDdevices 1011 then further undergo additional packaging operations tofurther improve the sealing formed by the frit seal 1071 and the top andbottom substrates 1061, 1002.

FIGS. 2 a, 3 a and 4 are plan views illustrating an organicelectroluminescence display device according to one embodiment of theinvention. FIGS. 2 b and 3 b are sectional views for illustrating FIGS.2 a and 3 a.

Referring to FIG. 2 a, a substrate 200 defines a pixel region 210 and anon-pixel region 220. The non-pixel region 220 may be a regionsurrounding the pixel region 210 or a peripheral region of the pixelregion 210. Multiple organic electroluminescence elements 100 are formedbetween a scan line 104 b and a data line 106 c on the pixel region 210of the substrate 200, and on the non-pixel region 220 of the substrate200 are formed a scan line 104 b and a data line 106 c extended from thescan line 104 b and the data line 106 c, respectively, of the pixelregion 210, a power supply line (not shown) for generating the organicelectroluminescence elements 100, and a scan driver 410 and a datadriver 420 for processing signals from the exterior through pads 104 cand 106 d and supplying them to the scan line 104 b and data line 106 c.

Referring to FIG. 2 b, the organic electroluminescence element 100comprises an anode electrode 108 a and cathode electrode 111, and anorganic thin film layer 110 formed between the anode electrode 108 a andcathode electrode 111. The organic thin film layer 110 is formed as astructure in which a hole transport layer, an organic light-emittinglayer and an electron transport layer are deposited, and may furthercomprise an hole injection layer and an electron injection layer.

In a passive matrix type display, the organic electroluminescenceelement 100 as configured above is connected in a matrix form between ascan line 104 b and a data line 106 c, and in an active matrix type, theorganic electroluminescence element 100 is connected in a matrix formbetween the scan line 104 b and data line 106 c, the active matrix typefurther comprising a thin film transistor (TFT) for controlling theorganic electroluminescence element 100 and a capacitor for sustaining asignal. The thin film transistor comprises a source, a drain and a gate.A semiconductor layer 102 provides a source and drain regions, to whicha source and drain electrodes 106 a and 106 b, and a channel region, onan upper side of which is a gate electrode 104 a electrically insulatedfrom the semiconductor layer 102 by a gate insulation film 103.

Referring to FIGS. 3 a and 3 b, on an encapsulation substrate 300 isformed a frit 320 along the surrounding of the encapsulation substrate300. The frit 320 encapsulates the pixel region 210 to inhibit oxygen ormoisture from penetrating therein, which is formed to surround at leasta part of the non-pixel region 220 including the pixel region 210 andmay be formed of a material, for example, such as a glass frit dopedwith at least one kind of transition metal, which may be fused by laserbeam or infrared ray.

Referring to FIG. 4, the encapsulation substrate 300 is arranged on theupper side of the substrate 200. The encapsulation substrate 300 isarranged on the upper side of the substrate 200 so as to be superposedto the pixel region 210 and a part of the non-pixel region 220. Aprotective film 108 b, which in one embodiment is made of the sameinorganic material as an anode electrode 108 a and is separated from theanode electrode 108 a, is provided between the frit 320 and a scan line104, a data line 106 c and a power supply line. The anode electrode 108a and protective film 108 b may be made of an opaque inorganic electrodematerial in the case of front surface light emitting type, and atransparent inorganic electrode material in the case of back surfacelight emitting type. The opaque inorganic electrode material may be aninorganic material selected from a group comprising, for example, ACX(alloy of Al), Ag, and Au, or a mixture thereof, and the transparentinorganic electrode may be an inorganic material selected from a groupcomprising, for example, ITO, IZO, and ITZO, or a mixture thereof. Alaser beam and/or infrared ray is irradiated under a condition where theencapsulation substrate 300 is attached onto the substrate 200, suchthat the frit 320 is fused and bonded to the substrate 200.

A manufacturing method of an organic electroluminescence display deviceconfigured as above will be described below with reference to FIGS. 5 athrough 5 g and FIGS. 6 a and 6 b in accordance with one embodiment.Referring to FIGS. 5 a and 6 a, a substrate 200 is prepared, on which apixel region 210 and a non-pixel region 220 are defined. The non-pixelregion 220 may be defined as a region surrounding the pixel region 210or a peripheral region of the pixel region 210. A buffer layer 101 isformed on the pixel region 210 and non-pixel region 220 of the substrate200. The buffer layer 101, which serves to inhibit the damage to thesubstrate 200 due to heat and isolate diffusion of ions from thesubstrate 200 to the outside, is formed as an insulating film such assilicon oxide film SiO2 and/or silicon nitride film SiNx.

Referring to FIG. 5 b, a semiconductor layer 102, which provides anactive layer, is formed on the buffer layer 101 of the pixel region 210,and a gate insulating film 103 is formed on the upper surface of thepixel region 210 and non-pixel region 220 including the semi conductorlayer 102. The semiconductor layer 102 provides a source and drainregions and a channel region for a thin film transistor.

Referring to FIG. 5 c, a gate electrode 104 a is formed on the gateinsulating film 103 placed on the upper side of the semiconductor layer102. On the pixel region 210 is formed a scan line connected to the gateelectrode 104 a and on the non-pixel region 220 are formed a scan line104 extended from the scan line 104 of the pixel region 210 and a pad104 c to receive signals from the exterior. The gate electrode 104 a,scan line 104 b and pad 104 c are made of metals such as Mo, W, Ti, Al,and/or alloys thereof, and can be formed as an stacking structure. Thenon-pixel region 220 of FIG. 5 c is a sectional surface of a part formedwith the scan line 104 b.

Referring to FIG. 5 d, a between-layer insulating film 105 is formed onthe upper surface of the pixel region 210 and non-pixel region 220including the gate electrode 104 a. Contact holes are formed throughwhich parts of the semiconductor layer 102 are exposed by patterning thebetween-layer insulating film 105 and gate insulating film 103, and asource electrode 106 a and a drain electrode 106 b are formed to beconnected through the contact holes to the semiconductor layer 102. Onthe pixel region 210 is formed a scan line connected to the gateelectrode 106 a and on the non-pixel region 220 are formed a scan line106 extended from the scan line 106 of the pixel region 210 and a pad104 c to receive signals from the exterior. The source and drainelectrodes 106 a and 106 b, data line 106 c and pad 106 d are made ofmetals such as Mo, W, Ti, Al, and/or alloy thereof, and formed as astacking structure. The non-pixel region 220 of FIG. 5 d is a sectionalsurface of a part formed with the data line 106 c.

Referring to FIGS. 5 e and 5 f and FIG. 6 b, a flattened layer 107 isformed on the upper surface of the pixel region 210 to flatten thesurface. A via hole is formed through which parts of the source or drainelectrode 106 a or 106 b are exposed by patterning the flattened layer107 of the pixel region 210. An electrode material layer made of aninorganic material is formed on the upper side of the pixel region 210and non-pixel region 220. The patterning is made so that on the pixelregion 210 is formed the anode electrode 108 a, which is connectedthrough the via hole to the source or drain electrode 106 a or 106 b,and on the non-pixel region 220 is formed the protective film 108 b. Thepatterning is performed so that the anode electrode 108 and protectivefilm 108 b have a separated structure for electrical isolation betweenthe scan electrode 104 b and data line 106 c and the anode electrode 108a. The non-pixel region 220 of FIG. 5 e is a sectional surface of a partformed with the scan line 104 b, and the non-pixel region 220 of FIG. 5f is a sectional surface of a part formed with the data line 106 c.

The electrode material layer made of an inorganic material may be madeof an opaque inorganic material or a mixture of inorganic materials inthe case of front surface light emitting type, and a transparentinorganic material or a mixture of inorganic materials in the case ofback surface light emitting type. The opaque inorganic material ormixture of inorganic materials may be selected from a group comprising,for example, ACX (alloy of Al), Ag, and Au, and the transparentinorganic or mixture of inorganic materials may be selected from a groupcomprising, for example, ITO, IZO, and ITZO.

In one embodiment, the flattened layer 107 is formed on the upper sideof the pixel region 210 and non-pixel region 220 and then to pattern theflattened layer 107 such that the pad 106 d connected to the data line106 c is exposed. In another embodiment, the flattened layer 107 isformed only on the pixel region 210 since the attachment to the dataline 106 may be less secure in a case where the flattened layer 107 ismade of an organic material.

Referring to FIG. 5 g, a pixel definition film 109 is formed on theflattened layer 107 so that a part of the anode electrode 108 a isexposed, and then an organic thin film 110 is formed on the exposedanode electrode 108 a and a cathode electrode 111 is formed on the pixeldefinition film 109 including the organic thin film layer 110.

This embodiment suggests a construction where the scan line 104 b, dataline 106 c and power supply line are not exposed by the protective film108 b made of an inorganic material. Although a construction issuggested where the protective film 108 b is formed on the surface ofthe non-pixel region 220 including the scan line 104 b, data line 106 cand power supply line, it is also possible to implement a constructionwhere the protective film 108 b is formed only on the scan line 104 b,data line 106 c and power supply line of the non-pixel region 220.

Turning again to FIGS. 3 a and 3 b, a encapsulation substrate 300 isprovided whose size is such an extent that a part of the pixel region210 is superposed to a part of the non-pixel region 220. A substratemade of a transparent material such as glass is employed as theencapsulation substrate 300, and in one embodiment a substrate made ofsilicon oxide SiO2 is employed.

The frit 320 is formed along the surrounding of the encapsulationsubstrate 300. The frit 320 encapsulates the pixel region 210 to inhibitoxygen or moisture from penetrating therein, which is formed to surrounda part of the non-pixel region 220 including the pixel region 210. Thefrit is in certain embodiments a powder-type glass material. In otherembodiments, a paste state of frit wherein a laser or infrared lightabsorber, an organic binder, a filler for reducing the thermal expansioncoefficient, etc., are included to facilitate curing after a firingprocess. For example, a frit may be doped with at least one kind oftransition metal.

Referring to FIG. 7, the encapsulation substrate 300 is arranged on theupper side of the substrate 200 manufactured through processes shown inFIGS. 5 a through 5 g. The frit 320 is attached to the substrate 200 byan irradiating laser beam or infrared ray along the frit 320 under acondition where the encapsulation substrate 300 is arranged on the upperside of the substrate 200 to be superposed to the pixel region 210 and apart of the non-pixel region 220. The laser beam or infrared ray is atleast partially absorbed by the frit, which in turn generates heat.Thereby the frit 320 is fused and attached to the substrate 200.

In one embodiment using the laser, the laser beam is irradiated on theorder of power of 36W to 38W, and is moved in a substantially constantspeed along the frit 320 so as to sustain a more uniform fusiontemperature and adhesive strength. In one embodiment, movement speed ofthe laser or infrared ray is on the order of 10 to 30 mm/sec, andpreferably, 20 mm/sec.

In one embodiment with respect to a case where the gate insulating film103 and between-layer insulating film 105 are formed on the pixel region210 and non-pixel region 220, it is also possible to form them only onthe pixel region 210. An embodiment has been described with respect to acase where the frit 320 is formed to seal only the pixel region 210, itis not limited thereto, but may be formed to include the scan driver410. In that embodiment, the size of the encapsulation substrate 300should also be appropriately changed. In addition, an embodiment hasbeen described where the frit 320 is formed on the encapsulationsubstrate 300, it is not limited thereto, but may also be formed on thesubstrate 200.

The organic electroluminescence display device according to oneembodiment allows the protective film 108 b to be made of an inorganicelectrode material to be formed on the upper side of metal wiring suchas the scan line 104 b, data line 106 c and power supply line in theprocedure that the anode electrode 108 a of the pixel region 210 isformed. Therefore, when a laser beam is irradiated to fuse and attachthe frit 320 to the substrate 200, metal wirings such as the scan line104 b, data line 106 c and power supply line placed in a lower side ofthe frit 320 and a part intersecting the frit 320 fail to be directlyexposed to heat due to the laser beam as shown in FIGS. 8 a and 8 b.

Reflectivity of the metals generally used as electrodes or wirings isCr(0.632), Mo(0.550), Ti(0.557), and W(0.500), but reflectivity of theopaque inorganic electrode materials used for this embodiment isrelatively high such as Al(0.868), Ag(0.969), Au(0.986), etc.Accordingly, since heat absorption ratio is low due to the highreflectivity, heat transfer to the metal wirings of the lower side maybe decreased.

In addition, the transparent inorganic electrode materials (ITO, IZO,ITZO, etc.) used for this embodiment, which are metal oxide, have evenlower heat conductivity compared to metallic materials, and thus mayserve to isolate heat transferred to the metal wirings of the lower sideand may serve as a buffer layer, thus making it possible to inhibitdamage to the metal wiring due to heat. Heat transfer is insulated bythe protective film 108 b and thus possible damage to the metal wiringsdue to heat is inhibited, which in turn inhibits the cracking of themetal wirings or substantial variation of self resistance and electricalproperties, thereby making it possible to sustain electrical propertyand reliability of elements.

As mentioned above, one embodiment allows the protective film made of aninorganic material to be formed on the upper side of metal wiring suchas the scan line, data line and power supply line in the procedure thatthe anode electrode is formed. The metal wirings of the lower side ofthe frit and the part intersecting the frit are not directly exposed toheat due to laser beam or infrared ray, and heat transfer is insulated,thus inhibiting any damage to the metal wirings due to heat. Therefore,cracks of the metal wirings or substantial variation of self resistanceand electrical properties are inhibited, thereby making it possible tosustain electrical property and reliability of elements.

In addition, since a protective film is formed by an inorganic materialhaving an outstanding adhesive strength with the frit on the metalwirings of the non-pixel region without addition of separate processesor mask, it is possible to give even more prominent adhesive strengththan the case where the frit is attached directly to the metal wirings.Thus, the adhesive strength is enhanced between the frit and substrate,which in turn inhibits the penetration of oxygen or moistureeffectively, thereby improving reliability of the display device.

FIGS. 9 a, 10 a and 11 are plan views of illustrating an organicelectroluminescence display device according to another embodiment FIGS.9 b and 10 b are sectional views for illustrating FIGS. 9 a and 10 a.Referring to FIG. 9 a, a substrate 600 defines into a pixel region 610and a non-pixel region 620. The non-pixel region 620 may be a regionsurrounding the pixel region 610 or a peripheral region of the pixelregion 610. Multiple organic electroluminescence elements 500 are formedbetween a scan line 504 b and a data line 506 c on the pixel region 610of the substrate 600, and on the non-pixel region 620 of the substrate600 are formed a scan line 504 b and a data line 506 c extended from thescan line 504 b and the data line 506 c, respectively, of the pixelregion 610, a power supply line (not shown) for generating the organicelectroluminescence elements 500, and a scan driver 810 and a datadriver 820 for processing signals from the exterior through pads 504 cand 506 d and supplying them to the scan line 504 b and data line 506 c.

Referring to FIG. 9 b, the organic electroluminescence element 500comprises an anode electrode 509 a and cathode electrode 512, and anorganic thin film layer 512 formed between the anode electrode 509 a andcathode electrode 511. The organic thin film layer 511 is formed as astructure in which an hole transport layer, an organic light-emittinglayer and an electron transport layer are deposited, and may furthercomprise an hole injection layer and an electron injection layer.

In a passive matrix type display, the organic electroluminescenceelement 500 as configured above is connected in a matrix form between ascan line 504 b and a data line 506 c, and in an active matrix typedisplay, the organic electroluminescence element 500 is connected in amatrix form between the scan line 504 b and data line 506 c, the activematrix type further comprising a thin film transistor TFT forcontrolling the organic electroluminescence element 500 and a capacitorfor sustaining a signal. The thin film transistor comprises a source, adrain and a gate. A semiconductor layer 502 provides a source and drainregions, to which a source and drain electrodes 506 a and 506 b, and achannel region, on an upper side of which is a gate electrode 504 aelectrically insulated from the semiconductor layer 503 by a gateinsulation film 502.

Referring to FIGS. 10 a and 10 b, on the encapsulation substrate 700 isformed a frit 720 along the surrounding of the encapsulation substrate300. The frit 720 encapsulates the pixel region 610 to inhibit oxygen ormoisture from penetrating therein, and is formed to surround at least apart of the non-pixel region 620 including the pixel region 610 and maybe formed of a material, for example, such as a glass frit doped with atleast one kind of transition metal, which may be fused by laser beam orinfrared ray.

Referring to FIG. 11, the encapsulation substrate 700 is arranged on theupper side of the substrate 600. The encapsulation substrate 700 isarranged on the upper side of the substrate 600 so as to be superposedto the pixel region 610 and a part of the non-pixel region 620. A firstprotective film 507 and a second protective film 509 b are provided in astacking structure between the frit 720 and the scan line 504 b, dataline 506 c and the power supply line formed on the non-pixel region 620.The first protective film 507 is formed of a silicon compound selectedfrom a group comprising SiOx, SiNx, SiOxNy, and the second protectivefilm 509 b is formed of an opaque inorganic electrode material in afront surface light emitting type, and a transparent inorganic electrodematerial in a back surface light emitting type. The opaque inorganicelectrode material may be an inorganic material selected from a groupcomprising, for example, ACX (alloy of Al), Ag, and Au, or a mixturethereof, and the transparent inorganic electrode may be an inorganicmaterial selected from a group comprising, for example, ITO, IZO, andITZO, or a mixture thereof.

The first protective film 507 and the second protective film 509 b maybe formed on the surface of the non-pixel region 620, and the secondprotective film 509 b may be formed of the same inorganic electrodematerial as the anode electrode 509 a. In a case where the secondprotective film 509 b is formed of the same inorganic electrode materialas the anode electrode 509 a, it should be separated from the anodeelectrode 509 a for the electrical isolation between the scan line 504 band data line 506 c and the anode electrode 509 a. A laser beam orinfrared ray is irradiated under a condition where the encapsulationsubstrate 700 is attached onto the substrate 600, such that the frit 720is fused and bonded to the substrate 600.

A manufacturing method of an organic electroluminescence display deviceconfigured as above will be described below with reference to FIGS. 12 athrough 12 h and FIGS. 13 a and 13 b in accordance with anotherembodiment. Referring to FIGS. 12 a and 13 a, a substrate 600 isprepared, on which a pixel region 610 and a non-pixel region 620 aredefined. The non-pixel region 620 may be defined as a region surroundingthe pixel region 610 or a peripheral region of the pixel region 610. Abuffer layer 501 is formed on the pixel region 610 and non-pixel region620 of the substrate 600. The buffer layer 501, which serves to inhibitthe damage to the substrate 600 due to heat and isolate diffusion ofions from the substrate 600 to the outside, is formed as an insulatingfilm such as silicon oxide film SiO2 and/or silicon nitride film SiNx.

Referring to FIG. 12 b, a semiconductor layer 501, which provides anactive layer, is formed on the buffer layer 502 of the pixel region 610,and a gate insulating film 502 is formed on the upper surface of thepixel region 610 and non-pixel region 620 including the semi conductorlayer 503. The semiconductor layer 502 provides a source and drainregions and a channel region for a thin film transistor.

Referring to FIG. 12 c, a gate electrode 504 a is formed on the gateinsulating film 502 placed on the upper side of the semiconductor layer503. On the pixel region 610 is formed a scan line connected to the gateelectrode 504 a and on the non-pixel region 620 are formed a scan line504 b extended from the scan line 504 b of the pixel region 610 and apad 504 c to receive signals from the exterior. The gate electrode 504a, scan line 504 b and pad 504 c are made of metals such as Mo, W, Ti,Al, or alloy thereof, and can be formed as an stacking structure. Thenon-pixel region 620 of FIG. 12 c is a sectional surface of a partformed with the scan line 504 b.

Referring to FIG. 12 d, a between-layer insulating film 505 is formed onthe upper surface of the pixel region 610 including the gate electrode504 a. Contact holes are formed through which parts of the semiconductorlayer 503 are exposed by patterning the between-layer insulating film505 and gate insulating film 502, and a source electrode 506 a and adrain electrode 506 b are formed to be connected through the contactholes to the semiconductor layer 502. At this time, on the pixel region610 is formed a data line 506 c connected to the source and drainelectrodes 506 a, 506 b and on the non-pixel region 620 are formed adata line 506 c extended from the data line 506 c of the pixel region610 and a pad 506 d to receive signals from the exterior. The source anddrain electrodes 506 a and 506 b, data line 506 c and pad 506 d are madeof metals such as Mo, W, Ti, Al, or alloy thereof, and formed as astacking structure. The non-pixel region 620 of FIG. 12 d is a sectionalsurface of a part formed with the data line 506 c.

Referring to FIGS. 12 e and 12 f, the first protective film 507 isformed on the upper surface of the non-pixel region 620 including thescan line 504 b and data line 506 c. The first protective film 507 isformed of a material including Si, selected from a group comprisingSiOx, SiNx, SiOxNy, etc., e.g., a silicon compound. The non-pixel region620 of FIG. 12 e is a sectional surface of a part formed with the scanline 504 b, and the non-pixel region 620 of FIG. 12 f is a sectionalsurface of a part formed with the data line 506 c.

Referring to FIGS. 12 g and 13 b, a flattened layer 508 is formed on theupper surface of the pixel region 610 to flatten the surface. A via holeis formed through which parts of the source or drain electrode 506 a or506 b are exposed by patterning the flattened layer 508 of the pixelregion 610. An electrode material layer made of an inorganic material isformed on the upper side of the pixel region 610 and non-pixel region620. Patterning is made so that on the pixel region 610 is formed theanode electrode 509 a, which is connected through the via hole to thesource or drain electrode 506 a or 506 b, and on the non-pixel region620 is formed the second protective film 509 b.

The electrode material layer made of an inorganic material may be madeof an opaque inorganic material or a mixture of inorganic materials inthe case of front surface light emitting type, and a transparentinorganic material or a mixture of inorganic materials in the case ofback surface light emitting type. The opaque inorganic material ormixture of inorganic materials may be selected from a group comprising,for example, ACX (alloy of Al), Ag, and Au, and the transparentinorganic or mixture of inorganic materials may be selected from a groupcomprising, for example, ITO, IZO, and ITZO.

In one embodiment, the second protective film 509 b is formed during theprocedure when the anode electrode 509 a is formed, so that additionalprocesses and mask will not required. In other embodiments, it is alsopossible to form the anode electrode 509 a and the second protectivefilm 509 b through separate processes. In a case where the anodeelectrode 509 a and the second protective film 509 b are formed asinorganic electrode material layers in the same process steps, the anodeelectrode 509 a and the second protective film 509 b have the separatedstructure for the electrical isolation between the scan line 504 b anddata line 506 c and the anode electrode 509 a.

Referring to FIG. 12 h, a pixel definition film 510 is formed on theflattened layer 508 so that a part of the anode electrode 509 a isexposed, and then an organic thin film 511 is formed on the exposedanode electrode 509 a and a cathode electrode 511 is formed on the pixeldefinition film 510 including the organic thin film layer 512. Thisembodiment suggests a construction where the scan line 504 b, data line506 c and power supply line are not exposed by the first protective film507 and the second protective film 509 b. Although a construction issuggested where the first protective film 507 and the second protectivefilm 509 b are formed to have a stacking structure on the surface of thenon-pixel region 620 including the scan line 504 b, data line 506 c andpower supply line, it is also possible to implement a construction wherethe first protective film 507 and the second protective film 509 b areformed only on the scan line 504 b, data line 506 c and power supplyline of the non-pixel region 620.

Turning again to FIGS. 10 a and 10 b, a encapsulation substrate 700 isprovided whose size is such an extent that at least a part of the pixelregion 610 is superposed to a part of the non-pixel region 620. Asubstrate made of a transparent material such as glass is employed asthe encapsulation substrate 700. In one embodiment, a substrate made ofsilicon oxide SiO2 is employed.

The frit 720 is formed along the surrounding of the encapsulationsubstrate 700. The frit 720 encapsulates the pixel region 610 to inhibitoxygen or moisture from penetrating therein, which is formed to surroundat least a part of the non-pixel region 620 including the pixel region610. In one embodiment, the frit is generally a powder-type glassmaterial. Another embodiment provides a paste state of frit, wherein alaser or infrared light absorber, an organic binder, a filler forreducing the thermal expansion coefficient, etc., can be included tofacilitate curing after a firing process. For example, a frit may bedoped with at least one kind of transition metal.

Referring to FIG. 14, the encapsulation substrate 700 is arranged on theupper side of the substrate 600 manufactured through processes shown inFIGS. 12 a through 12 h. The frit 720 is attached to the substrate 700by an irradiating laser beam or infrared ray along the frit 720 under acondition where the encapsulation substrate 706 is arranged on the upperside of the substrate 600 to be superposed to the pixel region 610 and apart of the non-pixel region 620. The laser beam or infrared ray is atleast partially absorbed by the frit 720, which in turn generates heat,and thereby the frit 720 is fused and attached to the substrate 600.

In embodiments using the laser, the laser beam is irradiated on theorder of power of 36W to 38W, and is moved in a generally constant speedalong the frit 720 so as to sustain a more uniform fusion temperatureand adhesive strength. In one embodiment, the movement speed of thelaser or infrared ray is on the order of 10 to 30 mm/sec, andpreferably, 20 mm/sec.

One the embodiment has been described where the frit 720 is formed toseal only the pixel region 610, it is not limited thereto, but may beformed to include the scan driver 810 in other embodiments. In theseembodiments, the size of the encapsulation substrate 700 should also beappropriately changed. In addition, embodiments have been describedwhere the frit 720 is formed on the encapsulation substrate 700, it isnot limited thereto, but may also be formed on the substrate 600.

The organic electroluminescence display device according to oneembodiment forms the first protective film 507 and the second protectivefilm 509 b to have a stacking structure on the metal wirings such as thescan line 504 b, data line 506 c and power supply line of the non-pixelregion 620. When a laser beam is irradiated to fuse and attach the frit720 to the substrate 600, the metal wirings 504 b, 506 c of a lower sideof the frit 720 and a part intersecting the frit 720 fail to be directlyexposed to heat due to the laser beam as shown in FIGS. 15 a and 15 b.The second protective film 509 b made of an inorganic electrode materialat least partially reflects laser beam out to inhibit heat from beingabsorbed. The first protective film 507 made of a silicon compoundsubstantially insulates heat from being transferred from the secondprotective film 509 b to the metal wirings 504 b, 506 c.

Reflectivity of the metals generally used as electrodes or wirings isapproximately Cr(0.632), Mo(0.550), Ti(0.557), and W(0.500).Reflectivity of the opaque inorganic electrode materials used forembodiments is relatively high such as for Al(0.868), Ag(0.969),Au(0.986), etc. Accordingly, since heat absorption ratio is low due tothe high reflectivity, the amount of heat transferred to the metalwirings of the lower side may be significantly lowered. In addition, thetransparent inorganic electrode materials (ITO, IZO, ITZO, etc.) usedfor certain embodiments, which are metal oxide, have even lower heatconductivity compared to metallic materials, and thus may serve toisolate heat transferred to the metal wirings of the lower side and mayserve as a buffer layer, thus making it possible to significantly reducedamage to the metal wiring due to heat. Accordingly, heat transfer iseffectively insulated by the first protective film 507 and the secondprotective film 509 b formed as a double structure and thus possibledamage to the metal wirings 504 b, 506 c due to heat is reduced, whichin turn inhibits cracking of the metal wirings or substantial variationof self resistance and electrical properties, thereby making it possibleto sustain electrical properties and reliability of elements.

In addition, since the second protective film 509 b is formed by aninorganic material having outstanding adhesive strength with the frit onthe metal wirings 504 b, 506 c of the non-pixel region 620 withoutaddition of separate processes or mask, it is possible to give even moreprominent adhesive strength than the case where the frit is attacheddirectly to the metal wirings 504 b, 506 c. Thus, the adhesive strengthis enhanced between the frit 720 and substrate, which in turn inhibitsthe penetration of oxygen or moisture more effectively, therebyimproving reliability of the display device.

One embodiment forms a protective film having a double structure on themetal wirings of the non-pixel region. Accordingly, the metal wirings ofthe lower side of the frit and the part intersecting the frit are notdirectly exposed to heat due to laser beam or infrared ray by aninorganic layer for reflecting laser beam to insulate heat from beingabsorbed and a silicon compound layer for insulating the heat transfer,and thus reducing possible damage to the metal wirings due to heat. Thisin turn inhibits cracking of the metal wirings or substantial variationof self resistance and electrical properties, thereby making it possibleto sustain electrical properties and reliability of elements.

In addition, since a protective film is formed by an inorganic materialhaving outstanding adhesive strength with the frit on the metal wiringsof the non-pixel region during forming the anode electrode withoutaddition of separate processes or mask, it is possible to give even moreprominent adhesive strength than the case where the frit is attacheddirectly to the metal wirings. Accordingly, the adhesive strength of thefrit is enhanced to thus inhibit oxygen or moisture from penetrating,making it possible to improve reliability of the display device.

Although embodiments of the invention have been shown and described, itwould be appreciated by those skilled in the art that changes might bemade without departing from the principles and spirit of the invention,the scope of which is defined in the claims and their equivalents.

1. An organic electroluminescence display device comprising: a firstsubstrate formed with organic electroluminescence elements and a metalwiring for transmitting signals to the organic electroluminescenceelements, each organic electroluminescence element comprising a firstelectrode, an organic thin film layer and a second electrode, whereinthe first electrode comprises a first material, a second substratearranged over the first substrate, a frit provided between the firstsubstrate and the second substrate such that the metal wiring isinterposed between the frit and the first substrate, and a protectivefilm formed of the first material and located between the metal wiringand the frit, the protective film being separated from the firstelectrode.
 2. The organic electroluminescence display device as claimedin claim 1, wherein at least one of the first substrate and the secondsubstrate comprises a transparent material.
 3. The organicelectroluminescence display device as claimed in claim 1, wherein themetal wiring comprises one selected from the group of a scan line, adata line, and a power supply line.
 4. The organic electroluminescencedisplay device as claimed in claim 1, wherein the protective film isformed on a region other than a pixel region formed with the organicelectroluminescence element.
 5. The organic electroluminescence displaydevice as claimed in claim 1, wherein the first material is one or moreselected from the group consisting of ACX, Ag, and Au.
 6. The organicelectroluminescence display device as claimed in claim 1, wherein thefirst material is one or more selected from the group consisting of ITO,IZO, and ITZO.
 7. The organic electroluminescence display device asclaimed in claim 1, wherein the frit comprises at least one dopant madeof transition metal.
 8. The organic electroluminescence display deviceas claimed in claim 1, further comprising transistors for controllingthe operation of the organic electroluminescence elements.
 9. Theorganic electroluminescence display device as claimed in claim 1,wherein the frit comprises one or more materials selected from the groupconsisting of magnesium oxide (MgO), calcium oxide (CaO), barium oxide(BaO), lithium oxide (Li₂O), sodium oxide (Na₂O), potassium oxide (K₂O),boron oxide (B₂O₃), vanadium oxide (V₂O₅), zinc oxide (ZnO), telluriumoxide (TeO₂), aluminum oxide (Al₂O₃), silicon dioxide (SiO₂), lead oxide(PbO), tin oxide (SnO), phosphorous oxide (P₂O₅), ruthenium oxide(Ru₂O), rubidium oxide (Rb₂O), rhodium oxide (Rh₂O), ferrite oxide(Fe₂O₃), copper oxide (CuO), titanium oxide (TiO₂), tungsten oxide(WO₃), bismuth oxide (Bi₂O₃), antimony oxide (Sb₂O₃), lead-borate glass,tin-phosphate glass, vanadate glass, and borosilicate.
 10. An organicelectroluminescence display device comprising: a first substratedefining a pixel region and a non-pixel region, wherein the pixel regionis formed with an organic electroluminescence element comprising a firstelectrode, an organic thin film layer and a second electrode, whereinthe first electrode comprises a first material, wherein the non-pixelregion is formed with a metal wiring for transmitting signals to theorganic electroluminescence element, a second substrate arranged overthe first substrate, a frit provided between the first substrate and thesecond substrate such that the metal wiring is interposed between thefrit and the first substrate, and first and second protective filmsinterposed between the metal wiring and the frit, wherein the secondprotective film is interposed between the frit and the first protectivefilm, wherein the second protective film comprises the first material.11. The organic electroluminescence display device as claimed in claim10, further comprising a transistor connected to the first electrode,the transistor comprising a source, a drain and a gate.
 12. The organicelectroluminescence display device as claimed in claim 10, wherein themetal wiring comprises one selected from the group consisting of a scanline, a data line, and a power supply line.
 13. The organicelectroluminescence display device as claimed in claim 10, wherein thenon-pixel region is formed with the first and second protective films.14. The organic electroluminescence display device as claimed in claim10, wherein the first protective film comprises a compound selected fromthe group consisting of SiOx, SiNx, and SiOxNy.
 15. The organicelectroluminescence display device as claimed in claim 10, wherein thesecond protective film is separated from the first electrode.
 16. Amanufacturing method of an organic electroluminescence display devicecomprising: providing a buffer layer over a first substrate, whichdefines a pixel region and a non-pixel region, providing a semiconductorlayer on the buffer layer of the pixel region and providing a gateinsulating film over the pixel region, providing a gate electrode and afirst portion of a first metal wiring on the gate insulating film of thepixel region and providing, on the gate insulating film of the non-pixelregion, a second portion of the first metal wiring connected to thefirst portion of the first metal wiring of the pixel region, providing abetween-layer insulating film over the pixel region and non-pixel regionand providing a contact hole so that a portion of the semiconductorlayer is exposed, providing, on the between-layer insulating film of thepixel region, source and drain electrodes and a first portion of asecond metal wiring connected through the contact hole to thesemiconductor layer and providing, on the between-layer insulating filmof the non-pixel region, a second portion of the second metal wiringconnected to the first portion of the second metal wiring of the pixelregion, providing a flattened layer over the pixel region and providinga via hole so that the source or drain electrode is exposed, providing afirst electrode comprising a first material over the pixel region, and aprotective film comprising the first material over the non-pixel region,wherein the first electrode is connected through the via hole to thesource or drain electrode, providing an organic thin film layer and asecond electrode over the first electrode, forming a frit over thesecond substrate, and arranging the second substrate over the firstsubstrate such that the frit is interposed between the first and secondsubstrates and that a portion of the protective film is interposedbetween the frit and one of the first and second metal wirings.
 17. Themanufacturing method of an organic electroluminescence display device asclaimed in claim 16, wherein the first electrode is separated from theprotective film.
 18. The manufacturing method of an organicelectroluminescence display device as claimed in claim 16, wherein thefirst material comprises one or more selected from the group consistingof ACX, Ag, and Au.
 19. The manufacturing method of an organicelectroluminescence display device as claimed in claim 16, wherein thefirst material electrode comprises one or more selected from the groupconsisting of ITO, IZO, and ITZO.
 20. The manufacturing method of anorganic electroluminescence display device as claimed in claim 16,wherein the frit is melted by at least one of a laser beam and aninfrared ray.
 21. The manufacturing method of an organicelectroluminescence display device as claimed in claim 16, wherein thefrit comprises at least one dopant made of transition metal.